July 10, 2018—KB4338819 (OS Build 17134.165)

Note This release also contains updates for Microsoft HoloLens (OS Build 17134.165) released July 10, 2018.

Improvements and fixes

This update includes quality improvements. No new operating system features are being introduced in this update. Key changes include:

Improves the ability of the Universal CRT Ctype family of functions to correctly handle EOF as valid input.

Enables debugging of WebView content in UWP apps using the Microsoft Edge DevTools Preview app that’s available in the Microsoft Store.

Addresses an issue that may cause the Mitigation Options Group Policy client-side extension to fail during GPO processing. The error message is “Windows failed to apply the MitigationOptions settings. MitigationOptions settings might have its own log file” or “ProcessGPOList: Extension MitigationOptions returned 0xea.” This issue occurs when Mitigation Options has been defined either manually or by Group Policy on a machine using Windows Defender Security Center or the PowerShell Set-ProcessMitigation cmdlet.

Evaluates the Windows ecosystem to help ensure application and device compatibility for all updates to Windows.

Addresses an issue that prevents devices on the Workstation Pro SKU from receiving the Windows 10, version 1803 update.

Known issues in this update

Symptom

Workaround

After installing this update on a DHCP Failover Server, Enterprise clients may receive an invalid configuration when requesting a new IP address. This may result in loss of connectivity as systems fail to renew their leases.

After you install any of the July 2018 .NET Framework Security Updates, a COM component fails to load because of “access denied,” “class not registered,” or “internal failure occurred for unknown reasons” errors. The most common failure signature is the following: